Rotary hydraulic motor

ABSTRACT

A rotary hydraulic motor including body structure and a vaned rotor journaled therein defining a plurality of the pressure chamber sections for reception of fluid under pressure from a common source, and valve means for controlling flow of fluid under pressure to one or a given plurality of said chamber sections selectively.

United States Patent 525,341 9/1894 Florenceetal.

Albln R. Erickson 409 3rd Ave. N.E., Roseau, Minn. 56751 881,420

Dec. 2, 1969 June 22, 1971 Inventor Appl. No. Filed Patented ROTARY HYDRAULIC MOTOR 1,671,750 5/1928 Staude. 418/209 2,345,920 4/1944 Douglas... 418/82 2,910,839 11/1959 Adams 418/267 3,035,554 5/1962 Selzler .1 418/267 3,086,475 4/1963 Rosaen..... 418/268 3,230,715 1/1966 Klein et al..... 418/267 3,451,346 6/1969 Pettibone 418/81 Primary Examiner-Carlton R. Croyle Assistant ExaminerWilbur J. Goodlin At1orney--Merchant& Gould ABSTRACT: A rotary hydraulic motor including body structure and a vaned rotorjournaled therein defining a plurality of the pressure chamber sections for reception of fluid under pressure from a common source, and valve means for controlling flow of fluid under pressure to one or a given plurality of said chamber sections selectively.

PATENTED JUH22 I971 SHEET 2 OF 3 INVENTOR. Emcnsa/v BY jgpz/ PATENTEDJUNZZIS?! 3586466 SHEET 3 OF 3 IN VENTOR. 'flw/vRER/mwu /Wei ROTARY HYDRAULIC MOTOR SUMMARY OF THE INVENTION An important object of this invention is the provision of a hydraulic motor which can be quickly and easily controlled to operate at different given speeds when driven by a constant delivery of hydraulic fluid.

Another object of this invention is the provision of a rotary hydraulic motor having a rotor and generally radial vanes car ried by the rotor and radially movable therein alternately in opposite directions by fluid pressure. Still another object of this invention is the provision of a hydraulic motor as set forth which is relatively simple and inexpensive to produce, which is highly efficient in operation, and which is rugged in construction and durable in use.

To the above ends, I provide a housing defining a generally cylindrical chamber havingaxially spaced end wall surfaces and a peripheral wall surface having alternating circumferentially spaced concavities and cylindrical surface portions. A cylindrical rotor is disposed in the chamber concentric with the cylindrical surface portions and includes an axial output shaft journaled in the housing and projecting axially therefrom. The rotor is provided with circumferentially spaced radial slots each radially slidably containing a different one of a plurality of vanes having outer ends slidably engaging the cylindrical surface portions and concavities, and opposite side edges slidably engaging the end wall surfaces of the chamber.

The housing and rotor cooperate to define a plurality of circumferentially spaced pressure chamber sections each having a fluid inlet port and an outlet port. The housing has a fluid inlet and an outlet, and defines passage means communicating with the inlet and outlet and with each inlet port and outlet port. A valve element in the housing is operable to admit fluid under pressure to one or more of the pressure chambers selectively to render a given number of the pressure chambers operative. The arrangement is such that, with a constant delivery of fluid input to the motor, a high speed relatively low torque output is obtained when fluid is admitted to a single pressure chamber section. By admitting fluid to more than one pressure section, lower output speed of the motor shaft at relatively higher torque is obtained.

The rotor slots have enlarged radially inner end portions that communicate with the fluid passage means in the housing, each of the vanes having piston-acting flanges in the enlarged slot portions, the passage means being arranged to admit fluid under pressure to opposite sides of the vane flanges selectively to move the vanes radially outwardly and inwardly at predetermined points of circumferential movement of the vanes.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in axial section of a rotary hydraulic motor produced in accordance with this invention;

FIGS. 2, 3, 4 and are views in transverse section, taken on the lines 2-2, 3-3, 4-4 and 5-5 respectively on FIG. 1, on a reduced scale; and

FIG. 6 is an enlarged view in perspective of one of the rotor vanes of this invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The hydraulic motor of this invention includes a generally cylindrical housing, indicated generally by the reference numeral l, the housing 1 including a main body member 2 and generally platelike front and rear end members 3 and 4 respectively, the members 2-4 being rigidly secured together by a plurality of circumferentially spaced nut equipped machine screws or like fastening members 5.

The main body member 2 and front end member 3 cooperate to define a generally cylindrical chamber 6 having axially spaced end wall surfaces 7 and 8 defined by the body member 2 and end member 3 respectively, and a peripheral surface having alternating circumferentially spaced concavities 9 and cylindrical surface portions 10. With reference particularly to FIG. 2, it will be seen that the concavities 9 and cylindrical surface portions 10 are, for the purpose of the present example, three each in number. A generally cylindrical rotor 11 is journaled in the chamber 6, having sliding engagement with the end wall surfaces 7 and 8 and with the cylindrical surface portions 10. The rotor II is splined or otherwise rigidly mounted on an axial drive shaft 12 that is journaled in bearings 12a and 12b in the main body member 2 and front end member 3 respectively, see FIG. 1. As shown by full lines in FIG. 2 and dotted lines in FIG. 3, the radially inwardly opening concavities 9 and peripheral surface of the rotor 11 cooperate to define circumferentially spaced crescent-shaped pressure chamber sections 13, I4 and 15.

The rotor 11 is formed to provide a plurality of circumferentially spaced radial slots 16, each having inner end portions 17 that areenlarged in a direction circumferentially of the rotor, see particularly. FIG. 2. A plurality of vanes 18 are radially slidably mounted one each in a different one of the slots 16 for engagement of their radially outer ends with the concavities 9 and cylindrical surface portions 10 during rotation of the rotor 11. At their radially inner ends, the vanes 18 are provided with piston-acting flanges 19 that slidably engage the side surfaces of the enlarged slot portions 17, for a purpose which will hereinafter be described. Each vane 18 is further provided with a radially inwardly projecting pin or lug 20 that is adapted to abuttingly engage the inner end of its respective enlarged slot portions 17 to limit radially inward movement of each vane I8.

The rear end member 4 is provided with an inlet 21 and an outlet 22 that are adapted to be connected to a pressure line and a return line respectively, not shown. The pressure line may be assumed to be connected to a constant delivery pump also not shown, and the return line may be assumed to be connected to a reservoir for hydraulic liquid, also not shown, but from which the pump draws the liquid in a conventional hydraulic circuit. The inlet 21- and outlet 22 are adapted to communicate with selected ones of the pressure chamber sections 13-15 through fluid passage means and suitable valve means. The main body member 2 and rear end member 4 cooperate to define a generally cylindrical valve chamber 23 in which is journaled a platelike valve element 24. The valve element 24 is splined or otherwise rigidly secured to the inner end of a valve control shaft 25 that extends axially through and is journaled in the end body member 4, the outer end of the control shaft 25 having mounted thereon a control handle 26 exterior of the housing 1. The control shaft 25 is provided with a plurality of circumferentially spaced recesses 27, one of which is shown in FIG. 1, that are adapted to selectively receive a spring pressed ball detent 28 mounted in a hub portion 29 of the end member 4 to releasably hold the valve element 24 in any selected one of a plurality of circumferentially spaced positions within the valve chamber 23.

The main body 2 is provided with inlet passages 30, 31 and 32 extending from a respective one of the chamber sections 13, 14 and 15 to the valve chamber 23. In like manner, discharge passages 33, 34 and 35 extend from the pressure chamber sections l3, l4 and 15 respectively to the valve chamber 23. With reference particularly to FIGS. 2 and 3, it will be seen that the inlet passages 3032 open into the valve chamber 23 in circumferentially equally spaced relationship and at equal distances radially from the axis of the rotor shaft 12. It will also be noted that the outlet passages 3335 are open into the valve chamber 23 in circumferentially equally spaced relationship and equidistant from the axis of the drive shaft I2, the radial spacing of the passages 33--35 at the valve chamber 23 from the shaft axis being less than that of the inlet passages 3032.

The valve element 24 is formed to provide a pair of axially outwardly opening annular grooves 36 and 37 that are in register with branch openings 33 and 39 respectively in the end member 4, the branch opening 38 establishing communication between the inlet 21 and the annular groove 36, the branch opening 39 establishing communication between the outlet 22 and the annular groove 37. Fluid passages so, 41 and 42 extend transversely through the valve element 2d from the annular groove 36, the passage 49 terminating in the opposite side of the valve element 24 in a relatively long circumferentially extended groove d3 that is register-able with the adjacent end of the inlet passage 30. The fluid passage 4i terminates at the opposite side of the valve element 24, in a relatively shorter circumferentially extended groove 44 that is disposed to register with the adjacent end of the inlet passage 31. The passage 42 is in the nature of a circular opening extending transversely through the valve element 24 and is positioned to register with the adjacent end of the inlet passage 32. By reference to FIG. 4, it will be seen that the fluid passages 40- 42 are equidistantly circumferentially spaced in the valve element 24. Other circumferentially equidistantly spaced fluid passages 415, as and 57 extend transversely through the valve element 24 from the annular groove 37, and terminate in the opposite side of the valve element 24 in circumferentially extending grooves 43, of equal circumferential length, each of the grooves 48 being registerable with the adjacent end of a different one of the outlet passages 33-35.

The valve element 24 may be rotated by the control handle 26 between a position wherein none of the grooves 43, 441 and 48, and the passage 42 are in registration with the adjacent ends of their respective inlet passages Sit-32 and outlet passages 3335, wherein no fluid under pressure is delivered to anyone of the pressure chamber sections l3-B5, and any one of several operative positions, wherein one or more of the pressure chamber sections l3l are included in a pressure circuit to cause rotation to be imparted to the rotor ill. In the position of the valve element 24 illustrated in FIG. 4, the grooves 43 and 414 and the passage 42 are in register with their respective inlet passages 39, 3E and 32, all of the grooves 48 being in register with their respective outlet passages 33, 341 and 35. With the valve element 243 thus positioned, fluid under pressure is delivered, from the constant delivery pump, not shown, to all of the pressure chamber sections 33, M and to impart rotation to the rotor El and drive shaft 12 in a counterclockwise direction with respect to FlGS. 2-4l. With hydraulic liquid flowing through all of the pressure chamber sections 113-15 simultaneously, and applying pressure against at least some of the vanes 118 in each of the pressure chamber sections, rotation of the rotor ill and drive shaft 12 is relatively slow, but the torque output is relatively high. Rotation of the valve element 24 in a clockwise direction with respect to FIG. 4 to move the fluid passage 42 out of registration with the adjacent end of its corresponding inlet passage 32 will shut off the supply of hydraulic liquid to the pressure chamber section 15, and all of the liquid will be directed to and through chamber sections 13 and M. Thus, the rotor lit and drive shaft 12 will be caused to rotate at a relatively greater speed, but the torque output will be reduced, inasmuch as fluid pressure is applied against a lesser number of vanes l8. Further rotation of the valve element 111 in a clockwise direction with respect to FIG. 41, will move the groove 44 out of registry with the adjacent end of the inlet passage 31, so that all of the hydraulic liquid delivered by the pump will be delivered to the pressure chamber section 13 only, causing the rotor 11 to rotate at a still higher speed with a correspondingly lower torque output. It will be appreciated that the recesses 27 in the valve control shaft 25 are circumferentially spaced so that the valve element 24 is releasably held in any selected one of its above mentioned positions, in addition to a neutral position wherein neither of the grooves 83 or 44, or the port 42 is in registry with the adjacent end of its respective inlet passage 30, 31 or 32. It will also be noted that in all operating positions of the valve element 24, the grooves 48 are in register with the adjacent ends of their respective outlet passages 33-3, whereby to prevent hydraulic liquid from being trapped within any one or more pressure chamber sections lS-IS which may not be in use during operation of the motor.

The end wall surface 7 of the chamber 6, radially inwardly of the peripheral surface of the rotor 11, defines a pair of radially spaced inner and outer rows of circumferentially elongated grooves, the grooves of the inner row thereof being indicated at 49, 50, 51, 52, 53 and 54. The grooves of the radially outer row thereof are indicated at 55, 56, 57, 58, 59 and 69, see particularly FIG. 3, wherein the grooves 496tl are shown by dotted lines. The grooves 49-54 inclusive are disposed to register with the radially inner ends of the enlarged slot portions 17 and the rotor 11, the radially outer grooves 55-60 inclusive being disposed to register with the radially outer ends of the enlarged portions 17, radially outwardly of the piston-acting flanges 19 on the vanes lltl. Each of the grooves 49-5 8 communicates with valve chamber 23 by means of an individual one of a plurality of circumferentially spaced transverse ports or circular openings 6t. In like manner, each of the grooves 55-60 communicates with the valve chamber 23 by an individual one of a group of circumferentially spaced transverse ports or circular openings 62.

Fluid under pressure is introduced to selected ones of the ports 61 and 62 by means of a fluid passage 63 connecting the valve chamber 23 to the inlet 21, and discharged from other selected ports 61 and 62 through a discharge passage 64 extending between the valve chamber 23 and the outlet 22, together with cooperating passages in the valve element 24, now to be described. Adjacent the rear end member 4, the valve element 24 is formed to provide a pair of concentric annular grooves 65 and 66 that are in register with the inlet and outlet passages 63 and 64 respectively. Branching grooves 67, 6%, 69, 7t), 71 and 72 extend generally radially inwardly from the annular groove 65 and connect with transverse passages 73, 74, 75, 76, 77 and 78 respectively extending through to the opposite side of the valve element 24. Other branching grooves 79, 30, 8t, 82, 83 and 84 extend generally radially outwardly from the annular groove 66 and terminate in respective transverse passages 85, 86, 87, 83, $9 and 99 that extend through the valve element 24 to the opposite side thereof. The passages 7376 communicate with respective circumferentially extending grooves9l, 92, 93 and 94. The transverse passages 35-90, and circumferential grooves 9l1 109 are disposed in circumferentially extended rows, the transverse passages 74, 76, 7%, 35, 87 and 89, and circumferential grooves 92, 94, 95, 97 and 99 being disposed in a circumferential row and to be in register with given ones of the ports 62 in the main body member 2. The transverse passages 73, 75, 77, 86, 88 and 90, and circumferential grooves 91, 93, 96, 98 and 1109 are disposed in a second circumferentially extended row and to be in register with given ones of the ports 61 in the main body member 2. The arrangement is such that, when one or more of the pressure chambers 13-1l5 are under operative pressure, fluid under pressure will be introduced to the grooves 49 54 of the inner row thereof to impart radially outward movement to the vanes 18 adjacent the inlet passages to the pressurized chamber sections; and to the grooves 55 60 to impart radially inward movement to the vanes 11!? adjacent the outlet passages of the pressurized ones of the chamber sections. Thus, each vane 18 is fluid pressure urged radially outwardly into sealing engagement with the concavity or concave surface 9 of each pressurized chamber section during initial movement of the vane 18 circumferentially across the pressurized chamber section, the vane being moved radially inwardly by fluid pressure at the circumferentially opposite end of the pressurized chamber section, to reduce the frictional load between each vane 18 and the inner peripheral surface portions of the chambei' 6 at areas wherein there is little or no circumferential pressure applied to the vanes 1153.

With reference to F IG. 4, it will be noted that the transverse passages 77 and 78 are devoid of circumferential grooves at the inner ends thereof. It will be further noted that the circumferential grooves 93 and 94 are of shorter circumferential length than the grooves 91 and 92 respectively the passages 77 and 78, and grooves '9l-94, being inlet grooves or passages, fluid under pressure is introduced to the inner ends of the vanes 18 to move the same radially outwardly only in the pressure chamber sections l3, 14 or 15 to which fluid is introduced under pressure to their respective inlet passages 30, 31 or 32. The grooves 96, 98 and 100 are of equal circumferential length as are the grooves 95, 97 and 99 so that, no matter whether one, two or three pressure chamber sections are being used, the vanes 18 are free to move or be moved radially without being hydraulically locked when occupying or moving through a nonpressurized chamber section.

The various transverse passages 73-78 and 85-90, as well as the circumferential grooves 91-100 are so disposed relative to the fluid passage 42 and grooves 43, 44 and 48 that, when only the groove 43 is in register with its cooperating inlet passage 30, only the pressure grooves 91 and 92 are in register with the ports 61 leading to the grooves 49 and 56, it being appreciated that the discharge grooves 48, 95 and 96 are in register with the outlet port 33 and grooves 50 and 55. When the valve element 24 is rotated to move the groove 44 into register with its cooperating inlet passage 31, to pressurize the chamber section 14, corresponding grooves 93 and 94 move into register with the ports 61 and 62 leading to the grooves 51 and 58 respectively. At this time both chamber sections 13 and 14 are pressurized as are the fluid systems for moving the vanes 18 radially inwardly and outwardly in the pressure chambers 13 and 14. When the valve element 24 is rotated to move the fluid passage 42 into registration with the inlet passage 32, all of the chamber sections l3, l4 and 15 are pressurized, as are all of the circuit portions for imparting move ments to the vanes 18.

From the above, it will be seen that, with a delivery of fluid under pressure to the inlet 21 of the motor at a constant rate, pressurizing a single chamber section, such as the chamber section 13, will cause the rotor l l to be rotated at a relatively high rate of speed and at relatively low torque. By pressurizing chamber sections 13 and 14, the fluid will flow through the motor at a slower rate of speed due to the greater passage area aflorded by two pressure chamber sections resulting in a slower speed of rotation of the rotor 11 but with a greater torque output. Obviously, when the valve element 24 is rotated to cause all three pressure chambers l3, l4 and 15 to be pressurized, the rotor 11 will be rotated at a still slower speed but with still greater torque output. it will be further appreciated that, if desired, valving may be accomplished by utilizing individual valves remote from the housing 1, where operating conditions require. Further, if desired, conventional reversing valve mechanism may be utilized if it is desired to reverse the direction of rotation of the rotor 11.

What I claim is:

l. A rotary hydraulic motor comprising:

a. a housing defining a generally cylindrical chamber having axially spaced end wall surfaces and a peripheral surface having alternating circumferentially spaced concavities and cylindrical surface portions;

b. a cylindrical rotor in said chamber having an axial drive shaft journaled in the housing, said rotor substantially slidably engaging said end wall surfaces and cylindrical surface portions and cooperating with said concavities to define a plurality of circumferentially spaced generally crescent-shaped pressure chamber sections, said rotor having a plurality of circumferentially spaced generally radial slots;

c. a plurality of vanes; one each generally radially slidably mounted in a different one of said slots for engagement with said cylindrical wall portions and concavities;

d. means for imparting movement to said vanes radially of said rotor;

c. said housing defining fluid passage means for connection to a source of fluid pressure and communicating with said pressure chamber sections; f. and valve means for controlling flow of flu|d to one of said pressure chamber sections and given groups of said pressure chamber sections selectively.

2. The rotary hydraulic motor defined in claim 1 in which said housing defines a valve chamber, said passage means communicating with said valve chamber, said valve means including a valve element movable in said valve chamber selectively to a plurality of positions to direct fluid selectively to said pressure chamber sections.

3. The rotary hydraulic motor defined in claim 1 in which said rotor slots have radially inner end portions enlarged in a direction circumferentially of the rotor, said means for imparting generally radial movement to the vanes comprising pistonacting flanges on said vanes slidable therewith in said enlarged slot portions, said fluid passage means including fluid passages communicating with each of said enlarged slot portions and with said valve means.

4. The rotary hydraulic motor defined in claim 3 in which said fluid passage means includes radially spaced inner and outer rows of circumferentially spaced passages in said housing in communication with said valve means and disposed to communicate with said enlarged slot portions respectively radially inwardly and outwardly of said piston-acting flanges, whereby said vanes are alternately moved radially inwardly and outwardly by fluid pressure.

5. The rotary hydraulic motor defined in claim 4 in which the passages of said inner and outer rows thereof comprise circular ports in said housing communicating with said valve means, and circumferentially elongated grooves in one of said end wall surfaces each' connected to a different one of said ports, said grooves being disposed to register with said enlarged rotor slot portions. 

1. A rotary hydraulic motor comprising: a. a housing defining a generally cylindrical chamber having axially spaced end wall surfaces and a peripheral surface having alternating circumferentially spaced concavities and cylindrical surface portions; b. a cylindrical rotor in said chamber having an axial drive shaft journaled in the housing, said rotor substantially slidably engaging said end wall surfaces and cylindrical surface portions and cooperating with said concavities to define a plurality of circumferentially spaced generally crescent-shaped pressure chamber sections, said rotor having a plurality of circumferentially spaced generally radial slots; c. a plurality of vanes, one each generally radially slidably mounted in a different one of said slots for engagement with said cylindrical wall portions and concavities; d. means for imparting movement to said vanes radially of said rotor; e. said housing defining fluid passage means for connection to a source of fluid pressure and communicating with said pressure chamber sections; f. and valve means for controlling flow of fluid to one of said pressure chamber sections and given groups of said pressure chamber sections selectively.
 2. The rotary hydraulic motor defined in claim 1 in which said housing defines a valve chamber, said passage means communicating with said valve chamber, said valve means including a valve element movable in said valve chamber selectively to a plurality of positions to direct fluid selectively to said pressure chamber sections.
 3. The rotary hydraulic motor defined in claim 1 in which said rotor slots have radially inner end portions enlarged in a direction circumferentially of the rotor, said means for imparting generally radial movement to the vanes comprising piston-acting flanges on said vanes slidable therewith in said enlarged slot portions, said fluid passage means including fluid passages communicating with each of said enlarged slot portions and with said valve means.
 4. The rotary hydraulic motor defined in claim 3 in which said fluid passage means includes radially spaced inner and outer rows of circumferentially spaced passages in said housing in communication with said valve means and disposed to communicate with said enlarged slot portions respectively radially inwardly and outwardly of said piston-acting flanges, whereby said vanes are alternately moved radially inwardly and outwardly by fluid pressure.
 5. The rotary hydraulic motor defined in claim 4 in which the passages of said inner and outer rows thereof comprise circular ports in said housing communicating with said valve means, and circumferentially elongated grooves in one of said end wall surfaces each connected to a different one of said ports, said grooves being disposed to register with said enlarged rotor slot portions. 